Telecommunication Systems: From Fax to Digital TV

The Power of Mobile Phone Users and Telecommunication Systems

Fax Technology

The fax is a system of telecommunications used to transmit data, either written or graphic information, via a telephone line. Once the target computer number is established and connected via the telephone line, the fax machine explores the information and converts it into electrical impulses. These impulses are transmitted via the telephone lines.

Radio Transmission

Radio is a system for transmitting sound through space. It is based on the diffusion of electromagnetic waves (Hertz) from a sender, their propagation through space, and uptake by a receiver.

Modulation Principles

The transmitter creates two types of waves:

• Carrier Wave: A wave of fixed and very high frequency.
• Modulator Wave: A wave of much lower frequency that corresponds to the sound to be broadcast.

Broadcasting and Frequency

Frequency is the number of cycles of a wave per unit of time, measured in Hertz. It is evident that the emission of electromagnetic waves circulating in space is very elevated. Therefore, the transmitter emits a specific frequency (the carrier wave) that the receiver selects to achieve the desired signal.

Television (TV)

TV is a system to transmit images from a distance along with the corresponding sound in the form of electromagnetic waves. The images and sound captured by the camera are converted into an electrical signal, transmitted, and reproduced by the television set.

Mobile Telephony

This involves wireless connection through the air. This service allows a user to call or receive calls from virtually anywhere using a mobile phone.

Cellular Structure

The geographic area intended to be covered by the telephone service is divided into small areas or cells. Each cell has its own antenna and a set of frequencies that will be used when users call within that area.

Digital Television

Digital TV uses the same principle as transmitting voice or music, but with an added difficulty: the amount of information. The number of bits needed to transmit sound information is relatively small, but the number of bits required to convey an image is spectacular—about one billion bits per second at a minimum.

Email

Email lets you send and receive text, images, sounds, and videos to any computer connected to the network with very high speed. With these features, it is not surprising that email has largely displaced conventional telecommunication systems such as postal mail or fax.

Chat

Chat allows writing and talking with many people around the world simultaneously, in real time, and without delays.

The Blog

A blog is a personal space for writing on the Internet. It is like a personal diary, but virtual. The author of the blog updates it regularly and introduces all the information they wish to share.

Radar System

The radar telecommunication system can detect objects at a certain distance through the emission of radio waves. The transmitter emits electromagnetic waves through an antenna. If these waves encounter an object, some are reflected, creating a signal that arrives at the receiver, is amplified, and displayed on a screen. This system is used, for example, to monitor traffic.